Nav: Home

Brain tissue structure could explain link between fitness and memory

May 01, 2017

CHAMPAIGN, Ill. -- Studies have suggested a link between fitness and memory, but researchers have struggled to find the mechanism that links them. A new study by University of Illinois researchers found that the key may lie in the microstructure of the hippocampus, a region in the middle of the brain involved in memory processes.

Aron Barbey, a professor of psychology, led a group of researchers at the Beckman Institute for Advanced Science and Technology at Illinois that used a specialized MRI technique to measure the structural integrity of the hippocampus in healthy young adults and correlated it with their performances on fitness and memory tests. They found that viscoelasticity, a measure of structural integrity in brain tissue, was correlated with fitness and memory performance - much more so than simply looking at the size of the hippocampus.

"Using a new tool to examine the integrity of the hippocampus in healthy young adults could tell us more about how this region functions and how to predict decline for early intervention," Barbey said. "By the time we look at diseases states, it's often too late."

Prior research led by Illinois psychology professor Neal Cohen, who is also a co-author on the new paper, demonstrated that the hippocampus is critical for relational memory and that the integrity of this region predicts a host of neurodegenerative diseases. To date, much research on the hippocampus' structure has focused on its size.

Studies in developing children and declining older adults have found strong correlations between hippocampal size and memory. However, size does not seem to matter as much in healthy young adults, said postdoctoral researcher Hillary Schwarb. The Illinois group looked instead at the microstructure of the tissue, using an emerging neuroimaging tool called magnetic resonance elastography. The method involves an MRI scan, but with a pillow under the subject's head vibrating at a very low amplitude - as gentle as driving on the interstate, Schwarb said. The vibration is the key to measuring the structural integrity of the hippocampus.

"It's a lot like sending ripples through a still pond - if there's some large thing like a boulder under the surface, the ripples are going to displace around it," Schwarb said. "We are sending waves through the brain and reconstructing the displacements into a map we can look at and measure."

The study, published in the journal NeuroImage, found that those who performed better on the fitness test tended to also perform better on the memory task, confirming a correlation the group had noticed before. But by adding the information on the structure of the hippocampus, the researchers were able to find a possible pathway for the link. They found that the subjects with higher fitness levels also had more elastic tissue in the hippocampus. The tissue structure, in turn, was associated with memory.

"We found that when the hippocampus is more elastic, memory is better. An elastic hippocampus is like a firm foam mattress pad that pops right back up after you get up," said study co-author Curtis Johnson, a former graduate researcher at the Beckman Institute who is now a professor at the University of Delaware. "When the hippocampus is more viscous, memory is worse. A viscous hippocampus is like a memory-foam mattress that holds its shape even after you get up."

The results suggest that the viscoelasticity of the hippocampus may be the mediating factor in the relationship between fitness and memory in healthy young adults.

"It also shows us that magnetic resonance elastography is a useful tool for understanding tissue microsctructure, and that microstructure is important to cognition," Schwarb said. "This provides us a new level of analysis for studying the human brain."
-end-
The Office of the Director of National Intelligence, Intelligence Advanced Research Projects Activity supported this work through grant number 2014-13121700004.

Editor's notes: To reach Aron Barbey, call 217-244-2551; email barbey@illinois.edu. To reach Hillary Schwarb, email hschwarb@gmail.com.

The paper "Aerobic fitness, hippocampal viscoelasticity, and relational memory performance" is available online.

University of Illinois at Urbana-Champaign

Related Memory Articles:

Taking photos of experiences boosts visual memory, impairs auditory memory
A quick glance at any social media platform will tell you that people love taking photos of their experiences -- whether they're lying on the beach, touring a museum, or just waiting in line at the grocery store.
Think you know how to improve your memory? Think again
Research from Katherine Duncan at the University of Toronto suggests we may have to rethink how we improve memory.
Improving memory with magnets
The ability to remember sounds, and manipulate them in our minds, is incredibly important to our daily lives -- without it we would not be able to understand a sentence, or do simple arithmetic.
Who has the better memory -- men or women?
In the battle of the sexes, women have long claimed that they can remember things better and longer than men can.
New study of the memory through optogenetics
A collaboration between Universitat Autònoma de Barcelona and Harvard University pioneers the increase of memory using optogenetics in mice in Spain.
Peppermint tea can help improve your memory
Peppermint tea can improve long-term and working memory and in healthy adults.
A new glimpse into working memory
MIT study finds bursts of neural activity as the brain holds information in mind, overturns a long-held model.
Memory ensembles
For over forty years, neuro-scientists have been interested in the biological mechanisms underlying the storage of the information that our brain records every day.
What is your memory style?
Why is it that some people have richly detailed recollection of past experiences (episodic memory), while others tend to remember just the facts without details (semantic memory)?
Watching a memory form
Neuroscientists at Rosalind Franklin University of Medicine and Science have discovered a novel mechanism for memory formation.

Related Memory Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Anthropomorphic
Do animals grieve? Do they have language or consciousness? For a long time, scientists resisted the urge to look for human qualities in animals. This hour, TED speakers explore how that is changing. Guests include biological anthropologist Barbara King, dolphin researcher Denise Herzing, primatologist Frans de Waal, and ecologist Carl Safina.
Now Playing: Science for the People

#SB2 2019 Science Birthday Minisode: Mary Golda Ross
Our second annual Science Birthday is here, and this year we celebrate the wonderful Mary Golda Ross, born 9 August 1908. She died in 2008 at age 99, but left a lasting mark on the science of rocketry and space exploration as an early woman in engineering, and one of the first Native Americans in engineering. Join Rachelle and Bethany for this very special birthday minisode celebrating Mary and her achievements. Thanks to our Patreons who make this show possible! Read more about Mary G. Ross: Interview with Mary Ross on Lash Publications International, by Laurel Sheppard Meet Mary Golda...